I am attempting to obtain the autocorrelations and partial autocorrelations and to perform the augmented Dickey-Fuller test on the first difference of variable OutputValue, which is indexed by time, country and sector. My panel data has output by 160 countries and 24 sectors over 55 years with missing data on some time and sectors in some countries. This has led Stata to believe that I am using multiple panels when I type the following:

foreach i in dOutputValue {
 ac `i', saving(acd`i', replace)
 pac `i', saving(pacd`i', replace)

My relevant commands preceding the above are as follows:
egen id = group(Country Sector) *There are 3456 unique values of id.
xtset id Time
format Time %ty
sort id Time
bysort id : gen dOutputValue=d.OutputValue
I would like to perform ac, pac and dfuller on dOutputValue. How should I go about this?  Thank you in advance!